Short Communucation: An arsenosugar as the major extractable arsenical in the earthworm Lumbricus terrestris

Abstract

AbstractEarthworms (Lumbricus terrestris) were investigated for arsenic compounds by high‐performance liquid chromatography inductively coupled plasma mass spectrometry MS. Total arsenic concentrations were 6.3 ± 0.4 mg kg−1 in the earthworms and 28.1 ± 1.9 mg kg−1 in the casts of the earthworms. Extraction of the samples removed ∼25% of total arsenic from the earthworm tissues, but only ∼0.7% from the casts. The major arsenic compound in the earthworm extracts was an arsenic‐containing carbohydrate (phosphate arsenosugar, ∼55%); glycerol arsenosugar, dimethylarsinic acid, methylarsonic acid, arsenate, and arsenite were also present as minor constituents. In the cast extracts, the two arsenosugars could also be detected in addition to some arsenate and arsenite. The identification of the phosphate arsenosugar was confirmed with liquid chromatography– electrospray‐mass spectrometry with detection of m/z 75 (As+) and m/z 483 [(M + H)]+; the data were identical with those recorded for authentic standard material. This is the first report of an arsenosugar as the major extractable arsenical in a terrestrial animal. Copyright © 2002 John Wiley & Sons, Ltd.